OEM 2007 GMC Sierra 1500 Intake Manifold

2007 GMC Sierra 1500 Parts Questions & Experts Answers

• Q: How to replace the lower intake manifold on 2007 GMC Sierra 1500?

  A: Draining the cooling system marks the first step to replace the lower Intake Manifold. Begin by removing the Ignition Coil assembly along with the fuel pipes/hoses and evaporative emission (EVAP) canister tube and heater hose clamp. Release the heater outlet hose clamp to free the hose from the Intake Manifold and apply the same procedure to the heater inlet hose at the Water Pump. First reposition the heater hoses and disconnect the engine wiring harness electrical connector from the Throttle Body along with the a/c pressure switch and A/C Compressor clutch if the vehicle has these components. First remove the engine harness clamp and the oil pressure sensor electrical connector while also disconnecting the control port injector module and the evap canister purge solenoid valve. Remove the bolts holding the engine wiring harness bracket along with its ground nut and wire from the right cylinder head while also removing the stud at its mounting point. First reposition the harness before eliminating the PCV Valve Hose along with power Brake Booster Vacuum Hose and Thermostat Housing radiator inlet hose. First remove the Water Pump inlet hose clamps before taking out the Water Pump inlet hose. Accessing the front Intake Manifold bolt requires removal of the Drive Belt and power steering (P/S) pump rear bracket nut while preserving the p/s pump and A/C Compressor on the bracket followed by p/s pump bracket bolt removal. To expose the front Intake Manifold bolt you should move the p/s pump bracket forward. Remove the lower Intake Manifold bolts and Intake Manifold itself while discarding the old gaskets. Perform a cleaning procedure followed by visual assessment of the lower Intake Manifold. When installing the new Intake Manifold position a 4.0 mm (0.157 in) adhesive patch across the Intake Manifold Gasket surface near the cylinder head opening and apply it while the adhesive is still fresh before gasket installation. Place the gasket onto the pins before spreading a 5 mm (0.197 in) adhesive bead across each gasket from front and rear engine block tops which should reach 13 mm (0.50 in) beyond the gasket surface. Attach the Intake Manifold while applying threadlock to the lower bolts when using existing fasteners. Tighten the bolts in the specified sequence using a three-step method: the bolts received initial tightening to 3 n.m (27 lb in) then to 12 n.m (106 lb in) before reaching their final torque range of 15 n.m (111 lb). Secure the p/s pump bracket in its rear position and tighten the bracket bolts and nuts to 41 n.m (30 lb ft). Reattach the Drive Belt along with the Water Pump inlet hose and radiator inlet hose and restore the power Brake Booster Vacuum Hose and PCV Valve Hose to their position. Position the engine wiring harness and bracket while installing the bracket stud first and tightening it to 25 n.m (18 lb ft) then tighten the rear bracket nut at the evap canister purge solenoid valve along with the ground nut and wire to 16 n.m (12 lb ft). The engine wiring harness bracket bolts require a torque of 12 n.m (106 lb in) before reinstalling the evap canister tube, oil pressure sensor connector and engine harness clamp. Reconnect the evap canister purge solenoid valve , map sensor, control port injector module , and a/c connectors when included in the vehicle configuration. To finish installation connect the engine wiring harness electrical connector to the Throttle Body and place the heater hoses before securing them with the heater hose clamp. Place fuel pipes/hoses and Ignition Coil assembly back into position before filling the cooling system.